Well, leveling my noob priest continued to be more fun that I remembered, and I was able to get him to level 16 before running out of rested xp and switching to my mage. Spirit Tap kept my mana full and a nice rotation of applying my shield, then Smite, Shadow Word: Pain and Mind Blast when up seemed to finish off the mobs nicely.
When I switched to my mage, after trying a fire spec for my last push of leveling to 20, I decided to switch back to frost. While I enjoyed killing the mobs a little faster as fire, if I pulled more than one, I was basically dead, so I made the switch back to frost. Definitely a huge improvement on leveling. And the addition of Evocation at level 20 has seriously reduced the need to drink repeatedly, which also helps. It's basically a frost bolt spam approach with the occasional Fire Blast build in for when they get close enough. Frostbite seems to proc often enough to keep the mobs from getting anywhere near me most of the time, and even if I do pull two or three mobs, it is easy enough to Frost Nova, sheep one, kill the other, bandage and then kill the sheep.
One thing I did discover - always a good idea to check to make sure there isn't some giant kodo standing right behind you before hitting Frost Nova - really seems to piss them off!
I was able to run my mage up to level 22 before again running out of rested xp and so I'll be switching to my shaman for a while, who is currently sitting at level 24. I do enjoy leveling with the Shaman. I'm leveling as enhancement, which seems to be the generally recommended approach. It's pretty easy and mana efficient - make sure you've got a shield up, pull with lightning, shock them when it's available and other than that, just pound 'em into the ground with your big two hander. The best shock spell to use seems to vary depending on what youv'e gotten most recently from the trainer - I like both Earth and Frost shock.
So, I'll see how far I can get the Shammy before running out of rested xp and switching to the Paladind, who is currently camped at level 28.
I have been debating this approach of doing a little bit on each toon. I think it is overall faster because it maximizes the use of rested xp, but it is a little less personally fulfilling because you don't see those huge increases in levels from week to week on any given toon. So the other possible approach would be to just start with my highest level non-80 and level them individually, in reverse order, starting with my level 60 hunter. I'm pretty sure I'd actually get more of my toons to 80 before the expansion that way, so I may yet change my approach. But in the meantime, I'm going to continue with this approach for the next week or so, just to see how it goes.
Oh, and I failed to mention on Tuesday that I did managed to get "the Hallowed" on my warlock main in about two days. No purple proto-drake for Joar though, as I don't have the Winter holiday, Elder or Children's week (because of my lack of PvP achievement for Children's week).